The plot was good. The bit I remember was Wolfgang's death- which still makes me cry even though I've seen it about five times now. Got me real hyped up for the finale.
Los Contrarios were creepy, thought, and were dealt with far too easily by the Shoebox Zoo. And why do copies of people to kill the originals if, the moment their counterpart dies, they die too? Seems a little pointless, but the episode as a whole was pretty good.